It happened around 11:00 Friday evening at the Wingate Apartments on the 100 block of Wert Avenue.
The fire was started in the attic of one unit and spread to the roof of others.
The flames were contained to the attic of four units.
Two units were vacant and the other two each had one occupant.
No injuries were reported but two occupants were displaced.
The fire was placed under control around 11:20 pm.
Still no word what sparked the blaze.